1. Material composition: special cementing agent for permeable concrete, crushed stone and water.

2. Mix proportion of three materials during construction: (by mass) water: cement: cementing agent: macadam =113: 310:100:100:1520.

3, mixing matters needing attention

(1) The special person shall be responsible for the material ratio on the construction site.

(2) Strictly control the water cement ratio, that is, control the water addition. Add water 2-3 times when stirring, and it is not allowed to add it all at once.

(3) In order to stir the materials evenly, the mechanical stirring time should be appropriately extended, but it should not be too long.

Step 4 transport

Permeable concrete is a dry concrete material with quick initial setting. The transportation time of the mixture is generally controlled according to the climatic conditions, and the transportation time is generally controlled within 10 minute. Don't stop during transportation, the car must be stable.

5, paving, casting molding

Permeable concrete belongs to dry concrete, which has fast initial setting and must be paved in time. The pavement is paved by large area blocks and grids, and the loose paving coefficient is 1. 1. Spread the mixture evenly on the working face, use a ruler to find out the flatness and control a certain degree of pan-slurry, and then use a flat vibrator or manual compaction. High frequency vibrator is not suitable for tamping. Finally smooth. Water can't be mixed together.

Precautions:

(1), the loose paving coefficient is the ratio of the paving height of the material to the actual height. According to the dry humidity of permeable concrete, it is generally between1.1-1.15.

(2) The vibration time of the plate vibrator should not be too long, so as to prevent segregation due to over-density.

(3), spread as quickly and correctly as possible.

(4) Due to the high porosity and fast water loss of permeable concrete, when the temperature is higher than 35℃, the construction time should be avoided at noon, and it should be constructed in the morning and evening.

6. Expansion joint

After the construction of pervious concrete, according to the air temperature, when the strength of pervious concrete is greater than: 5Mpa, cut the expansion joint with a slit cutter and fill the joint with flexible joint materials.

7. Maintenance

After paving, after inspection, the elevation and flatness meet the requirements, plastic film should be covered immediately, or water should be used for curing, and the curing period should be not less than 7d, so that the strength can be gradually improved during the curing period.

Sprinkle water for maintenance. Watering and curing shall be started 1 day after pervious concrete is poured, and it shall start at 8 hours at high temperature. However, when spraying water, it is not advisable to spray water directly on the concrete surface with pressure water, but directly from top to bottom. The wet curing time of permeable concrete shall not be less than 7 days.

The curing time should be determined according to the construction temperature. The curing period is generally 14-2 1 day, the high temperature is not less than 14 days, the low temperature is not less than 2 1 day, and the construction below 5℃ is not less than 28 days.

8. Apply transparent sealant

After the surface concrete is molded and dried for about 3 days, transparent sealant is applied to enhance durability and aesthetics. Prevent time pollution and plug the cracks in permeable concrete.